This invention relates to a flashing light warning apparatus of a type having a voltage source, a main gate (or isolation, or barrier) transformer, a flash tube, an ignition device, at least one storage condenser, and an electrical switching device.
A flashing light warning apparatus of a type including a voltage source, a main gate transformer, a flash tube, an ignition device, at least one storage condenser, and an electrical switching device is well known from U.S. Pat. No. 3,644,818 to Paget. The flashing light warning apparatus of that patent includes two storage condensers, one of which is arranged in series with an electrical switching device. When the electrical charged with the same charging voltage from the main gate transformer. When the electrical switching device is open, the first storage condenser is charged somewhat more slowly than the second storage condenser via a resistor. By this means, electrical energy fed to the flash tube, and thereby light flash energy is influenced dependent upon the condition of the electrical switching device such that the light flash energy is reduced when the switching device is open.
This known light flash warning device has, however, a disadvantage in that light flash energies less than 50 mWs (milliwatt-seconds, or milli-joules are not achievable because the first storage condenser as well as the second storage condenser, upon operation of the light flash warning apparatus will be continuously charged and then discharged through the flash tube. The resistor which causes a slower charging of the first condenser, results only in a somewhat reduced charge on the first storage condenser when the gate transformer is turned off after a predetermined time period, such as, for example, once the second storage condenser is charged, thereby requiring an expensive, or difficult, control of the gate transformer. However, even then, if the first storage condenser is charged and discharged over the flash tube, a light energy is emitted from the flash tube which greatly disturbs and sometimes makes unuseful flight operations involving use of night vision apparatus, otherwise known as night-vision goggles (NVG).
Thus, a purpose of this invention is to provide a flashing light warning apparatus which is uncomplicated and can be cost-effectively produced and which while producing dependable light flashes allows a switching of a light energy level between nighttime and daytime flashes so that a night flash has a light energy level which can be viewed from afar only with night vision apparatus.